#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>

int Fib(int n)
{
	if (n == 2 || n == 1)
		return 1;

	else
		return Fib(n - 1) + Fib(n - 2);
}
int main() 
{
	int n = 0;
	scanf("%d,&n");
	int ret = Fib(n);
	return 0;
}